18 Transactions British Mycological Society. 
‘ 
and under Clavaria similis Boud. & Pat. describe the “‘spores 
hyalines a guttule huileuse, subsphériques, hérissées d’aiguillons 
coniques, 4-7 x 4:5” and further add that this species is 
“plus commun que Clavaria inaequalis.”’ Thus if we allowed 
Cotton’s contention to prevail we should have the absurdity of 
Clavaria inaequalis (Miull.) Fr. being represented by an echinu- 
late spored species in England and a smooth spored species in 
France. I may also add that I possess a painting made by my 
wife in 1889 of a Clavaria which I referred to inaequalis (Mill.) 
Fr. and this had smooth, globose spores, 6-7 » in diam., so it 
would seem clear that we also have the smooth spored form 
and it is probably not uncommon as I do not suppose that even 
one per cent. of these specimens are ever subjected to micro- 
scopical examination. 
We have had numerous presidential addresses and papers 
showing the great progress that has been made in the study of 
the Uredinales, Ustilaginales and Perisporiales. We now know 
that many of the biological species on our cereals are confined 
to one host and it is only occasionally by means of a bridging 
species that they are enabled to attack another host: that 
certain strains of our cereals are immune or less liable to be 
affected, this immunity depending not so much on the in- 
ability. of the spores of the parasite to effect an entrance but 
is rather due to some reaction on the host’s part, probably in 
the nature of an enzyme, that arrests their further development. 
In 1904 Eriksson brought forward his well-known mycoplasm 
theory as the cause of epidemical rust and mildew outbreaks 
that otherwise could not be explained. His view is that this 
mycoplasm exists as a form of protoplasm within the cells of 
the host and that it lives symbiotically in the tissues of the 
plant until such time as favourable conditions, climatic and 
others, cause it to pass into the typical mycelial stage from 
which the spore-beds of the Uredo are formed. Great advances 
have been made by numerous workers in our knowledge of the 
hetcroeciousrusts and the ‘‘ Monographia Uredinearum”’ by P. and 
H. Sydow contains an exhaustive account of this group, most of 
which has been embodied in W. B. Grove’s “‘ British Rust Fungi’”’ 
published in 1913. For a reliable list of the British Uredinales 
we are indebted to Mr J. Ramsbottom who prepared the list 
for our 1912 Transactions (see Trans. Brit. Myc. Soc. Iv, 98). 
I know of no real progress being made during this period with 
regard to a reclassification of the Pyrenomycetae, which is at 
present based, as you all know, on an artificial scheme almost 
as crude in character as the Linnean system was for phanero- 
gams: but notwithstanding this crudeness it is rather a remark- 
able fact and one I think to be deplored that no British text- 
